You might change your security settings on Facebook to hide all personal information and share wall posts and pictures only to people you know. However, even small traces of information like your Facebook "likes", which can be easily accessed by anyone online, can reveal your race, age, intelligence, sexuality, personality and even political views, according to a study conducted by researchers from the University of Cambridge.

The study used data on Facebook "likes", which, similar to browsing history and search queries, falls under generic class of information, according to the researchers. The study shows how sensitive information about a person can be extracted by seemingly harmless data.

The study included researchers from Cambridge's Psychometrics Centre and Microsoft Research Cambridge. Researchers analyzed a dataset of over 58,000 U.S. Facebook users. These users had volunteered to give researchers access to their Facebook "likes", profiles and psychometric testing results via an application called myPersonality.

Facebook "likes" were then analyzed using algorithms and this was then compared with information from profiles and other personality tests. Statistical models were then created to see if personality traits and other information can be predicted.

Researchers found that their statistical model can predict male sexuality with an accuracy of nearly percent; 95 percent accurate results were found in predicting a person's race. Similarly, a person's religious views (Christian or Muslim), political ideology (Democrat or Republican) could be found with over 80 percent accuracy.

The study could reveal information about parents' marital status, which might be difficult to find in other circumstances. The study could tell whether or not the user's parents divorced before the user turned 21 years of age with a 60 percent accuracy.

"We believe that our results, while based on Facebook Likes, apply to a wider range of online behaviours," said Michal Kosinski, Operations Director at the Psychometric Centre, one of the study authors.

Previous research has shown that Facebook is addictive, sometimes even more than sex and that not being a Facebook user is considered as being a threat to the society. Other studies have associated Facebook use with anxiety, debt and even higher weight.

The present study shows how social media sites can make people share personal information. Although information like this could provide accurate data for a large-scale study on human behavior (with millions across the world using the site), the same data can also pose a threat to online privacy of people.

"I am a great fan and active user of new amazing technologies, including Facebook. I appreciate automated book recommendations, or Facebook selecting the most relevant stories for my newsfeed. However, I can imagine situations in which the same data and technology is used to predict political views or sexual orientation, posing threats to freedom or even life," Kosinski added, according to a news release.

"I have used Facebook since 2005, and I will continue to do so. But I might be more careful to use the privacy settings that Facebook provides," David Stillwell, from Cambridge University, said.